Play games about the fish in the Baltic Sea

In our first documentary ”For Cod's Sake”, we talk about the problems with overfishing the predators in the seas. Discuss how this effects over fertilization. One third of the species in the Baltic Sea are marine, like cod and herring, and two thirds are freshwater fish, like perch. 259 different species have been registered in the swedish fresh- and salt waters. 142 of them are common native species and the remaining 117 are only known from rare findings or a few scattered individuals that have gone astray from other areas.

There are several games at saveourbalticsea.com under the tab education. Let your students learn about the inhabitants of the sea compete in our online games! Make it a competition within the class and choose an appropriate prize.

Common fish in the Baltic sea

European perch (Perca fluviatilis)

The green perch is easy to recognize. The dark stripes that decorate the sides and the red fins are characteristic. The belly is a yellowish white. The color shifts depending on what type of water it lives in. They can be light green or almost black. The dorsal fins are very sharp and easy to cut yourself on. The scale of the perch are strong and can be tough to remove. The perch can reach a weight of 4,7 kilos and a length of 51 cm. Although it doesn't normally grow any larger than half a kilo in our waters, and the female is larger than the male. All perch, regardless of age or size, have seven stripes.

Atlantic cod (Gadus morhua)

Atlantic cod used to be the North Sea and the Baltic Sea's most important fish for consumption along with herring. The cod usually resides at a deep of 5-600 meters. It can grow to 2 meters in length and weigh up to 96 kilograms (210 lb). It can live for 25 years and sexual maturity is generally attained between ages 2 to 4, but can be as late as 8 years in the northeast Arctic. Colouring is brown to green with spots on the dorsal side, shading to silver ventrally. A lateral line is clearly visible.

Bream (Abramis brama)

The common bream is a European species of freshwater fish in the family Cyprinidae. The common bream lives in ponds, lakes and canals, and in slow-flowing rivers. It has a laterally flattened and high-backed body and a slightly undershot mouth. It is a silvery grey colour,though older fish can be bronze-coloured especially in clear waters. The fins are greyish to black, but never reddish. The bream is at most 80 cm long and weighs 11 kg. The common bream lives in schools near the bottom. At night common bream can feed close to the shore and in clear waters with sandy bottoms feeding pits can be seen during daytime. The fish's protractile mouth helps it dig for chironomid larvae, Tubifex worms, bivalves, and gastropods.

Haddock (Melanogrammus aeglefinus)

The Haddock has a barbel (mustache/beard) just like the cod, but is distinguished by its lighter color. Haddock is most commonly found at depths of 40 to 133 m (130 to 436 ft). It thrives in temperatures of 2 to 10 °C (36 to 50 °F). Juveniles prefer shallower waters and larger adults deeper water. Generally, adult haddock do not engage in long migratory behavior as do the younger fish, but seasonal movements have been known to occur across all ages. Haddock feed primarily on small invertebrates, although larger members of the species may occasionally consume fish. Haddock is also a very popular food fish, sold fresh, smoked, frozen, dried, or to a small extent canned. Haddock, along with cod and plaice, is one of the most popular fish used in british fish and chips.

Goby (Gobiidae)

Gobies usually have a cylinder-like, long body, a thick head with eyes on top and a large mouth. They are usually small fish, about 10 cm long with large, tall fins. The most distinctive aspects of goby morphology are the fused pelvic fins that form a disc-shaped sucker. Gobies can often be seen using the sucker to adhere to rocks and corals, and in aquariums they will happily stick to glass walls of the tank, as well.

Gobies are primarily fish of shallow marine habitats including tide pools, coral reefs, and seagrass meadows; they are also very numerous in brackish water and estuarine habitats, including the lower reaches of rivers, mangrove swamps, and salt marshes. The color of a goby is modest, usually sand colored with a pattern as camouflage. Several small species only have a small amount of pigment and are transparent.

Lumpsucker (Cyclopterus lumpus)

Lumpsuckers are named appropriately enough; their portly bodies are nearly spherical with generally drab coloration and lithic patterns. The "sucker" part refers to the fish's modified pelvic fins, which have evolved into adhesive discs (located ventrally, behind the pectoral fins); the fish use these discs to adhere to the substrate. Many species have bony, wart-like tubercles adorning the head and body; these are important taxonomic features of the family.

As their appearance might suggest, lumpsuckers are poor swimmers. Most species are benthic; that is, they spend most of their time on or near the bottom. The fish are found on rocky or muddy substrates, where their coloration allows for effective camouflage.

Herring (Clupea harengus)

Herring is one of the most abundant fish species on earth. The largest known herring to be caught in the Baltic Sea was 51 cm and weighed over a kilo. They feed on copepods, krill and small fish, while their natural predators are seals, whales, cod and other larger fish. Atlantic herring can school in huge numbers. They aggregate in groups that consist of thousands to hundreds of thousands or even millions of individuals. All underwater recordings show herring constantly cruising reaching speeds up to 108 centimeters (43 in) per second, and much higher escape speeds.

Northern pike (Esox lucius)

The pike is the domineering predator in the swedish fresh- and brackish waters, and a popular fish for recreational fishing. The pike has a long, thin body with the dorsal fin far down on its back, a large head with a big mouth full of sharp teeth. It is a body made for hunting! The pike always swallows its prey whole, and can effortlessly devour fish up to half of its own length. It is constructed in a way that it can't spit anything out once it has started to swallow, because of its backward facing teeth. Whatever prey it catches has little chance of escape once bitten. This can however be to disadvantage of the pike since it could choke if it catches prey far too large.

Your choice matters 

– Labels that indicate good fish and fair treatment of animals

If you ask questions and put pressure to your school, restaurants or supermarkets you become part of the development towards a more sustainable fishing and farming industry. If you for example choose the eco-labels available when buying fish or other items you help create a larger demand for environmentally friendly supplies. Discuss the advantages with using sustainable methods without negative consequences for the environment. For example when they pass new laws against using chemicals and antibiotics.